scholarly journals The role of tectonics and hydrothermalism in early human evolution at Olduvai Gorge

2019 ◽  
Author(s):  
Ainara Sistiaga ◽  
Fatima Husain ◽  
David Uribelarrea ◽  
David Martín-Perea ◽  
Manuel Domínguez-Rodrigo ◽  
...  
Keyword(s):  
Human Evolution ◽  
Hot Springs ◽  
Dietary Quality ◽  
Tectonic Activity ◽  
Olduvai Gorge ◽  
Future Studies ◽  
Geochemical Evidence ◽  
Early Human ◽  
Critical Aspects

AbstractHominin encephalization has been at the centre of debates concerning human evolution with a consensus on a greater role for improved dietary quality. To sustain the energetic demands of larger brains, cooking was likely essential for increasing the digestibility and energy gain of meat and readily available, yet toxic starches. Here, we present the oldest geochemical evidence for a landscape influenced by tectonic activity and hydrothermal features that potentially shaped early hominin behaviour at Olduvai Gorge. Although use of fire at this time is controversial, hot springs may have provided an alternative way to thermally process dietary resources available in the 1.7 Myo Olduvai wetland. Our data supports the presence of an aquatic-dominated landscape with hydrothermal features that offered hominins new opportunities to hunt and cook readily available tubers and herbivore prey at the emergence of the Acheulean technology. Future studies should further examine whether hydrothermalism similarly influenced other critical aspects of human evolution.

Mesophyll conductance: the leaf corridors for photosynthesis

2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Main Role ◽  
Mesophyll Conductance ◽  
Future Studies ◽  
Cell Structures ◽  
Leaf Tissues ◽  
Change Framework ◽  
Chloroplast Stroma

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.

Motives for Social Isolation Following a Negative Emotional Episode

2018 ◽  
Vol 77 (3) ◽  
pp. 127-131
Author(s):  
Gérald Delelis ◽  
Véronique Christophe
Keyword(s):  
Social Isolation ◽  
Social Affiliation ◽  
Semantic Categorization ◽  
Future Studies ◽  
Cognitive Regulation ◽  
Emotional Event ◽  
Regulation Strategies ◽  
Emotional Events

Abstract. After experiencing an emotional event, people either seek out others’ presence (social affiliation) or avoid others’ presence (social isolation). The determinants and effects of social affiliation are now well-known, but social psychologists have not yet thoroughly studied social isolation. This study aims to ascertain which motives and corresponding regulation strategies participants report for social isolation following negative emotional events. A group of 96 participants retrieved from memory an actual negative event that led them to temporarily socially isolate themselves and freely listed up to 10 motives for social isolation. Through semantic categorization of the 423 motives reported by the participants, we found that “cognitive clarification” and “keeping one’s distance” – that is, the need for cognitive regulation and the refusal of socioaffective regulation, respectively – were the most commonly and quickly reported motives for social isolation. We discuss the findings in terms of ideas for future studies aimed at clarifying the role of social isolation in health situations.

scholarly journals Special Issue: The Role of Complement in Cancer Immunotherapy

Antibodies ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 29
Author(s):  
Ronald P. Taylor
Keyword(s):  
Cancer Immunotherapy ◽  
Complement System ◽  
Immune Defense ◽  
Special Issue ◽  
The Complement System ◽  
Critical Aspects

The complement system plays an important role in critical aspects of immune defense and in the maintenance of homeostasis in the bloodstream, as well as in essentially all tissues and organs [...]

Microstructure of high-temperature (>73 °C) siliceous sinter deposited around hot springs and geysers, Yellowstone National Park: the role of biological and abiological processes in sedimentation

2003 ◽  
Vol 40 (11) ◽  
pp. 1611-1642 ◽  
Author(s):  
Donald R Lowe ◽  
Deena Braunstein
Keyword(s):  
High Temperature ◽  
Yellowstone National Park ◽  
National Park ◽  
Hot Springs ◽  
Strain Effect ◽  
Temperature Sinter ◽  
Architectural Features ◽  
Siliceous Sinter ◽  
High Temperature Sinter

Slightly alkaline hot springs and geysers in Yellowstone National Park exhibit distinctive assemblages of high-temperature (>73 °C) siliceous sinter reflecting local hydrodynamic conditions. The main depositional zones include subaqueous pool and channel bottoms and intermittently wetted subaerial splash, surge, and overflow areas. Subaqueous deposits include particulate siliceous sediment and dendritic and microbial silica framework. Silica framework forms thin, porous, microbe-rich films coating subaqueous surfaces. Spicules with intervening narrow crevices dominate in splash zones. Surge and overflow deposits include pool and channel rims, columns, and knobs. In thin section, subaerial sinter is composed of (i) dark brown, nearly opaque laminated sinter deposited on surfaces that evaporate to dryness; (ii) clear translucent silica deposited subaqueously through precipitation driven by supersaturation; (iii) heterogeneous silica representing silica-encrusted microbial filaments and detritus; and (iv) sinter debris. Brownish laminations form the framework of most sinter deposited in surge and overflow zones. Pits and cavities are common architectural features of subaerial sinter and show concave-upward pseudo-cross-laminations and micro-unconformities developed through migration. Marked birefringence of silica deposited on surfaces that evaporate to dryness is probably a strain effect. Repeated wetting and evaporation, often to dryness, and capillary effects control the deposition, morphology, and microstructure of most high-temperature sinter outside of the fully subaqueous zone. Microbial filaments are abundant on and within high-temperature sinter but do not provide the main controls on morphology or structuring except in biofilms developed on subaqueous surfaces. Millimetre-scale lamination cyclicity in much high-temperature sinter represents annual layering and regular seasonal fluctuations in silica sedimentation.

scholarly journals “Les copains *dit au revoir”: On Subject–Verb Agreement in L2 French and Cross-Linguistic Influence

Languages ◽  
2020 ◽  
Vol 6 (1) ◽  
pp. 7
Author(s):  
Malin Ågren ◽  
Marie-Eve Michot ◽  
Cyrille Granget ◽  
Sonia Gerolimich ◽  
Pascale Hadermann ◽  
...  
Keyword(s):  
Second Language Acquisition ◽  
Oral Narrative ◽  
Complex Interplay ◽  
Verb Morphology ◽  
Future Studies ◽  
Proficiency Levels ◽  
Verb Agreement ◽  
Significant Difference ◽  
L2 Development

This study focuses on the production of subject–verb (SV) agreement in number in L2 French and investigates the role of cross-linguistic influence (CLI) in this particular morphosyntactic domain. CLI is a well-known phenomenon in Second Language Acquisition (SLA) research but it has rarely been investigated systematically in relation to SV agreement in French. The participants of the study are 114 learners with Italian, German, Dutch and Swedish as L1. The source languages are all inflectional languages but they vary in terms of morphological richness in the verb paradigm, ranging from very poor (Swedish) to very rich (Italian). The participants performed an oral narrative task contrasting singular and plural contexts of SV agreement. Results indicate a significant difference between L1 groups in terms of correct SV agreement but they also show that the overall presence of rich verb morphology in the L1 does not, on its own, result in a more correct SV agreement. It is when comparing learners at two different proficiency levels that we observe differences in the rate of L2 development, which may be explained as an effect of CLI. Overall, results indicate a complex interplay of different factors, where the role of CLI must be further investigated in future studies in relation to L2 French.

Erratum: FeAs2 biomineralization on encrusted bacteria in hot springs: an ecological role of symbiotic bacteria

2004 ◽  
Vol 41 (4) ◽  
pp. 481
Author(s):  
Kazue Tazaki ◽  
Islam ABM Rafiqul ◽  
Kaori Nagai ◽  
Takayuki Kurihara
Keyword(s):  
Hot Springs ◽  
Symbiotic Bacteria ◽  
Ecological Role

Group Selection in the Evolution of Religion: Genetic Evolution or Cultural Evolution?

2015 ◽  
Vol 15 (3-4) ◽  
pp. 235-253 ◽  
Author(s):  
Taylor Davis
Keyword(s):  
Human Evolution ◽  
Cultural Evolution ◽  
Group Selection ◽  
Genetic Group ◽  
Genetic Evolution ◽  
Psychological Traits ◽  
Religious Psychology ◽  
Religious Evolution ◽  
The Relationship

In the scientific literature on religious evolution, two competing theories appeal to group selection to explain the relationship between religious belief and altruism, or costly, prosocial behavior. Both theories agree that group selection plays an important role in cultural evolution, affecting psychological traits that individuals acquire through social learning. They disagree, however, about whether group selection has also played a role in genetic evolution, affecting traits that are inherited genetically. Recently, Jonathan Haidt has defended the most fully developed account based on genetic group selection, and I argue here that problems with this account reveal good reasons to doubt that genetic group selection has played any important role in human evolution at all. Thus, considering the role of group selection in religious evolution is important not just because of what it reveals about religious psychology and religious evolution, but also because of what it reveals about the role of group selection in human evolution more generally.

Southeast African climate variability and early human evolution pulses

2016 ◽  
Vol 404 ◽  
pp. 208-209
Author(s):  
M.H. Simon ◽  
M. Ziegler ◽  
I.R. Hall ◽  
S. Barker ◽  
C. Stringer
Keyword(s):  
Climate Variability ◽  
Human Evolution ◽  
African Climate ◽  
Early Human

scholarly journals The Japanese empathy questionnaire (EmQue) for preschool children: Psychometric properties and measurement invariance across gender

2021 ◽  
pp. 016502542110228
Author(s):  
Reina Takamatsu ◽  
Yung-Ting Tsou ◽  
Takashi Kusumi ◽  
Carolien Rieffe
Keyword(s):  
Preschool Children ◽  
Measurement Invariance ◽  
Japanese Version ◽  
Developmental Models ◽  
Future Studies ◽  
Human Motivation ◽  
Confirmatory Factor ◽  
High Measurement ◽  
Gender Groups

Empathy is assumed to be a universal human motivation to act altruistically toward others. Developmental models of empathy explaining when and how children acquire the capacity to empathize have been proposed. However, the existing knowledge is largely built upon studies conducted in the Western context. To fill this gap, a cross-culturally validated measure of empathy for children is needed. The purpose of this study was to assess the Japanese version of the Empathy Questionnaire (EmQue), a parent-reported measure of empathy in preschool children, including its construct validity, measurement invariance across genders, and reliability. A total of 550 children aged 1–6 years participated in this study ( M age = 4.17 years, SD = 1.21). Their mothers completed the Japanese EmQue. Confirmatory factor analysis confirmed the hypothesized three-factor structure (emotional contagion, attention to others’ feelings, and prosocial actions) in the 13-item Japanese EmQue. The internal consistencies of the three scales were high. Measurement invariance across gender groups was also supported. Overall, the results demonstrate that the Japanese EmQue is a reliable and valid measure of the empathy of Japanese preschool children. It can serve as a tool in future studies to elucidate the role of culture in shaping empathy in early childhood.

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